Personally, I’ll take the third position — I’ll assert that market is the most important factor in a startup’s success or failure.
In a great market — a market with lots of real potential customers — the market pulls product out of the startup.
Sound advice. However, given the recent troubles Ning has been having, I found this part more than a little ironic (emphasis added):
In my experience, the most frequent case of great team paired with bad product and/or terrible market is the second- or third-time entrepreneur whose first company was a huge success. People get cocky, and slip up. There is one high-profile, highly successful software entrepreneur right now who is burning through something like $80 million in venture funding in his latest startup and has practically nothing to show for it except for some great press clippings and a couple of beta customers — because there is virtually no market for what he is building.
Sometimes even our own advice is difficult for us to adhere to.